Resistance thermometer: Iron coil in liquid Nitrogen and flame varies current.

5D20.15 • D+55+6

diagram for demo

Resistance thermometer: Iron coil in LN2 and flame varies current. A 6 volt battery sends about 2.5 amps through an iron coil (1.8 at room temperature). If the coil is heated with a bunsen burner flame, the resistance rises, and the current falls. If the coil is submersed in liquid nitrogen, the resistance falls, and the current rises dramatically.

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